Hey Atroz, hey Julian, hey all,
You need to use the correct formula if you refer to the VFD output / spindle input current, because it is three-phase electricity. The formula of three-phase current differs from the formula of single-phase AC. See here for details.
Also what matters here is the input current of the VFD, not the VFD output current / spindle input current. Unfortunately, it is often willingly omitted by the VFD manufacturers of cheap chinese VFD manufacturers:
As explained above, for a 2.2 kW mechanical power at the end of the shaft you need more than 3.2 kVA, plus VFD loss. There exist VFDs with a step-up converter, like the Huanyang “B-T” Models or the Invertek Optidrive ODE-3-210058-104# , but they are much more expensive than normal VFDs.
Julian @OneCNC, are you in North America? Usually you have split-phase electricity in the U.S. domestic areas which means 120 V between one hot and one neutral, and 240 V between the two hots, for radiators, oven, heaters, air conditioners etc. And for table saw and spindles. Better let an electrician install a NEMA 14 or NEMA 6 socket with 240 V and run your VFD/spindle directly.